Stonylab Nylon Membrane Filters, Hydrophilic Nylon Membrane Disc Filters With Description StonyLab engages in providing premium products to customers. We provide 12 months limited warranty and promise for excellent customer service. Please do not hesitate to contact us for any questions or concerns. We are always here to assist. StonyLab nylon membrane filters are ideal to use in chromatography and a wide range of biological preparations to retain particles, filter samples, vacuum degassing, and more; suitable for aqueous, HPLC, and most organic solvent 50-pack 3.7 inches diameter and 0.45 ?m pore size Nylon membrane is hydrophilic and has high protein binding as well as great chemical resistance Warranty: StonyLab 1-year limited warranty; if received damaged, please contact us immediately; we will solve it until satisfied